Shares of NeoPhotonics Corp. NPTN, -15.31% were indicated down nearly 7% in premarket trade, extending the previous session’s 21% plunge, after MKM Partners analyst Michael Genovese cut his rating on the optical equipment maker and slashed his price target in half, following the Trump administration’s moves to ban business with China’s Huawei Technologies. Genovese downgraded NeoPhotonics to neutral from buy, and lowered his stock fair value estimate to $4.50 from $9.00, given that Huawei is the company’s largest customer, representing about 46% of sales in 2018. He said he “holds out hope” that there is a 50% probability that the ban is walked back as part of a trade agreement, which would then turn the recent selloff into a great buying opportunity. The stock has tumbled 38.5% over the past three months, while the Nasdaq Composite COMP, -0.34% has gained 5.7% and the S&P 500 SPX, -0.06% has edged up 3.6%.

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